Rotational set well packer device

ABSTRACT

A packer apparatus that is set with low friction counter-clockwise rotation, and unset with clockwise rotation. A drain valve is opened concurrently as the packer apparatus is unset and closed as the packer apparatus is set. The Packer apparatus requires a minimum of parts and is designed to be used in corrosive environments.

CROSS-REFERENCE TO RELATED APPLICATIONS

Provisional Patent Application

Ser. No. 60/664,844 Filed Mar. 23, 2005

Entitled “ROTATIONAL SET WELL PACKER DEVICE”

Inventor: Harold Dean Clifton

-   -   Midland , Tex. 79707

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

REFERENCE TO A MICROFICHE APPENDIX

Not Applicable

BACKGROUND

This patent application discloses to those skilled in the art a rotational set packer device for use in oil and gas exploration and production.

The packer device of this invention is of the type that is insertable from the top of a well, which usually will be into a well casing, or other conduit. The packer device broadly comprises means, usually known in the oil field as a packer device or packer apparatus having expansible, resilient packer elements. The packer device is considered a downhole tool forming a part of a tool string for use in isolating various parts of a wellbore or borehole.

Packer devices are widely used in the oil field for isolating different elevations of the borehole from one another. One example of a packer device is set forth in U.S. Pat. No. 3,800,781, issued Apr. 12, 1974 to inventor Billy Ray Watson. Reference is made to the Watson patent and to the art cited therein for further background of this invention.

SUMMARY OF THE INVENTION

Oil field tools, especially packer devices or packer apparatus, are fabricated with right hand or clockwise rotation for setting the resilient packer elements thereof, whereupon fluid flow thereacross is precluded. One primary function of a packer device as described herein is to arrange the packer elements in series respective the tubing string whereby the annulus formed between the production tubing and the well casing prevents uphole flow of well fluid when the packer elements are expanded and set into engagement with the wall of the casing, thereby filling the annulus between the tubing and casing, whereupon both uphole and downhole flow of well fluid is prevented.

Packer apparatus often remain downhole for extended lengths of time and when the time arrives to remove the tool string for one reason or another, the deleterious affects of the well fluids may have corroded the various coacting parts of the packer apparatus, making it difficult to unscrew the components of the packer that unseat or relax the packer elements.

Packer apparatus usually form a component of a tool string wherein there may be a tubing anchor, and other components such as a gas separator and a production pump, for example only, arranged in series relationship. Usually, such a tool string is made up as the recited components thereof are introduced into the casing at the well head or Christmas Tree. Consequently, when downhole problems arise, the packer and the tubing anchor must be unseated, or released from engagement with the casing, otherwise the production tubing along with the tool string cannot be retrieved without resorting to costly fishing expedients.

In order to overcome these difficulties, several novel improvements are set forth in this disclosure.

When unseating the resilient packer elements of a prior art packer device having clockwise rotation of the tubing string for setting, the torque is effected upon the entire tubing string and this action is liable to disconnect most any of the threaded joints of the tool string that are located above the hold-down. In such a catastrophe, it would then be necessary to call in the experts to fish for whatever is stuck downhole.

Consequently, it is desirable to have available a unique packer device which is set by counterclockwise rotation with a torque force less than the force required to unscrew the joints of the tubing string as well as other tools of the tool string. When the packer device of this invention is located above the hold down, as shown in the Figures of the drawings, there can be no separation of the threaded connections of the various tools located therebelow, regardless of the direction of rotation required to unscrew various parts thereof.

Those skilled in the art, after digesting this entire disclosure, will appreciate that this disclosed packer device can be run above a tubing anchor along with other tools, such as a gas separator hookup, for example. This invention includes equalizing or drain ports that facilitate running and pulling the packer. In the present packer apparatus, approximately three turns left are required to set the packer elements, and right hand rotation to release the packer elements. The tubing can be placed in tension, compression or neutral. Low torque is required for setting the packer elements, and there are no slips or moving parts to wear out from pump movement. When desired, two packers can be run in the same string to isolate a zone for pumping, and furthermore, this packer can be run below a casing leak or perforations, and preferably is fabricated of stainless steel to further avoid the likelihood of corroded threads.

When the packer elements of this disclosure are set with counterclockwise rotation of the tubing string, the clockwise torque that must be effected on the tubing string cannot disconnect any of the threaded connections in the string when the packer device is located immediately above the hold-down, or tubing anchor.

Accordingly, a primary object of the present invention is the provision of a packer apparatus that can be run downhole to a selected elevation and set by rotating the supporting upper part of the packer counterclockwise respective a lower part thereof.

Another object of this invention is the foregoing packer apparatus that has upper and lower mandrels rotatable clockwise in order to unseat the packer device.

Still another object of this invention is a packer apparatus or packer device that forms a part of a tool string, has an axial passageway longitudinally extending therethrough, and further includes a valve device that is closed upon setting the packer elements thereof with a counterclockwise rotation between coacting parts thereof.

A further object of this invention is the provision of a packer apparatus that can be run downhole to a selected elevation and set by rotating the supporting upper part of the packer counterclockwise respective a lower part thereof and furthermore contains upper and lower mandrels rotatable clockwise in order to unseat the packer device; and further includes a valve device that is closed upon setting the packer elements thereof with a counterclockwise rotation between coacting parts thereof.

A still further object of this invention is the provision of a new combination of apparatus that include a packer device that is set by rotating part of the packer device in a counterclockwise direction and is unseated by rotating the last said part clockwise, in combination with a tubing anchor having selected prior art tools such as for example, a gas separator associated therewith.

These and other objects of the invention are attained in accordance with the present invention by the provision of a combination of elements which are fabricated in a manner substantially as claimed and described herein.

These and other objects and advantages of the present invention will become readily apparent to those skilled in the art upon reading the following detailed description and claims and by referring to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

While the invention is claimed in the concluding porions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying drawings where like parts in each of the several diagrams are labeled with like numbers:

FIG. 1 of the drawings is a part diagrammatical, part schematical representation of an oil well having disclosed therein the assembled packer tool of various embodiments of this invention;

FIG. 2 of the drawings is an enlarged part cross-sectional, part elevational, schematical representation of the assembled packer tool of one embodiment of this invention;

FIG. 3 is an enlarged representation of a side elevational view of the assembled packer tool of the preferred embodiment of this invention; and,

FIG. 4 illustrates a side elevation of the combination of the packer device and hold-down of this disclosure.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 of the drawings diagrammatically discloses a producing well bore 10 formed through the surface of the earth and extends downhole through a fluid producing formation F. There is a surface pipe or upper casing 11 for protecting the upper aquifer. Within surface casing 11 there is axially received a main well casing 12 extending downhole into proximity of the bottom 13 of the borehole. Production tubing 14 is also axially received respective casings 11 and 12. Accordingly, an annulus 16 is formed between casing 12 and tubing 14. Tubing 14 is a production pipe string, sometime referred to as a tool string for it is series connected respective to various oil field apparatus such as, for example only, the instant packer device 18, made in accordance with this invention, the details of which are more fully described later on herein.

The surface casing 11, well casing 12, and production tubing 14 are attached to a wellhead 17, also called a Christmas tree.

The tubing string 14, also referred to as a tool string 14, therefore discloses the packer apparatus 18 of this invention, a tubing hold-down 20 having slips 21, and other downhole apparatus such as a pump 22, as well as various other tools as may be desired or required.

As seen in FIG. 2, together with other figures of the drawings, the packer device 18 of this invention has annular packer elements 24, 24′ spaced from one another. The packer elements 24, 24′ are expansible, resilient, annular bodies made of an elastomeric product such as vulcanized rubber.

Looking now to FIG. 3 of the drawings, the uppermost end of upper mandrel 26 terminates in a box end 28 which is adapted to threadedly engage a complementary threaded end of production string 14, and a lower end 30 having a threaded marginal pin end received respective an upper threaded box end, seen at 32, of a lower mandrel 34. The lower mandrel 34 has an upper circumferentially extending enlarged terminal end portion 36; with the lower end of the lower mandrel terminating at pin end 38, thereby forming the lowermost end of packer device or apparatus 18.

An element compressor 40 of annular configuration is threadedly affixed to the upper mandrel 26 by the illustrated coacting threaded surface illustrated at 41 and therefore is considered a removable part of the upper mandrel 26. The element compressor 40 terminates in an upper circumferentially extending end 42 which abuttingly engages the illustrated external complementary shoulder formed on the upper mandrel.

The lower end 44 of element compressor 40 encloses the reduced diameter part of rubber packer elements 24, 24′ and acts as a seal as it bears against the illustrated packer elements.

An outwardly directed circumferentially extending groove 46 receives a carrier brass screw 46′ in low friction relationship therewithin and admits axial movement of element compressor 40 respective lower mandrel 34 to thereby compress the pair of confroning packer elements 24, 24′ responsive to rotation of the upper mandrel respective the lower mandrel.

An annular equalizing chamber 48 is formed between the upper mandrel 26 and the element compressor 40 as shown in FIG. 2. Within equalizing chamber 48 there is slidably received in a reciprocating manner the before mentioned enlarged upper marginal terminal end 36 of the lower mandrel 34. Inner and outer equalizing ports 50, 52, respectively, are formed in members 26, 40, respectively, and thereby complete the fluid flow path from within the tool string, through inner port 50, into chamber 48, and out of outlet port 52 when the packer is in the illustrated running in or unseated configuration of FIG. 2, thus enabling flow from the tubing string into the annulus 16 in order to drain or equalize the tool string upon unseating of the packer apparatus 18.

The opposed ends of an annular element spacer 54 engages similar complementary confronting ends of the packer element and separates the two packer elements 24, 24′. The element spacer 54 is slidably received in close tolerance relationship about the lower mandrel to transmit the resultant compressive forces that occur as the upper and lower mandrels are screwed together at low friction left-hand threaded surface 32.

A lower gauge 56, in the form of an inverted annular cap, threadedly engages the lower mandrel 34 by means of a threaded surface 58. Disposed within the gauge or cap 56 is an annular ring 60 that bears against reduced diameter lower sealing end 62′ of the lower packer element 24′ as follower 61 is urged against the lower mandrel and gauge responsive relative rotation between the upper and lower mandrels; which effectively lengthens and shortens the distance between the lower edge 44 of the element compressor 40 and gauge 56, and thereby compresses or relaxes the packer elements, which also sets and unseats the packer.

As pointed out above and claimed herein, the packer device can be used in combination with a downhole pump and tubing anchor, and often a gas separator hookup is advantageously included by connecting the recited apparatus in series relationship with respect to one another. An important feature of this invention is the provision of equalizing ports arranged to be closed and opened, respectively, in response to the rotation of the tubing string to move the packer elements into the set and unseated configuration, respectively, and thereby facilitate running and pulling the packer with a dry string. The packer is set by rotating the tubing from above the ground approximately 3 turns to the left; and opposite rotation of the tubing to the right for release.

CATALOG OF PARTS

-   10 producing wellbore -   11 surface casing -   11′ surface of earth -   12 main casing -   13 lower end of casing 12 -   F formation -   P perforations -   14 tubing string -   14′ outlet for 14 -   15 lower end of 14 -   16 annulus -   16′ outlet for upper annulus -   18 packer of this invention -   20 tubing hold down -   21 slips of 20 -   22 Downhole pump and other tools -   24 elements are expansible resilient packer rubber -   24′ as 24 -   FIG. 2: -   26 upper mandrel -   28 upper box end, threaded -   30 lower end of 26 -   32 threaded to engage 34 -   34 lower mandrel -   36 upper circumferentially extending end of 34 -   38 pin end forming the lower end of packer 18 -   40 element compressor -   42 upper end abuts external shoulder on 26 -   44 lower end encloses reduced diameter part of elements 24, 24′ -   46 locking groove -   46′ carrier brass screw received within 46 admits moving 40 axially     concurrently respective to movement of 26. -   47′ set screw received within 40 preventing relative axial movement     of 40/26 -   48 equalizing chamber -   50 inner port connected to 48 -   52 outer port connected to 52 -   54 element spacer -   56 lower gauge in form of a cap -   58 threads attaching 56 to 34 -   60 ring -   61 seal ring or follower -   62, 62′ lip seal received within complementary cavities -   66 pumping string -   68 side string -   70 gas separator or other tool     end catalog parts 

1. A rotational set well packer device for insertion into a conduit from the top of a wellbore, comprising a longitudinally extending tubular member forming a central axial passageway and having an expandable annular packer element supported thereon and projecting radially from the tubular member and blocking fluid flow up and down the annular space formed between the tubular member and a surrounding well conduit, said tubular member being separable into upper and lower mandrels, said upper mandrel being telescopingly received within said lower mandrel; counterclockwise complementary threads formed between the upper and lower mandrel for extending and retracting the upper mandrel respective the lower mandrel responsive to relative rotation therebetween; an annular cap mounted on the lower mandrel, an annular element compressor mounted on the upper mandrel and enclosing the upper marginal end of the lower mandrel to form a variable chamber between the element compressor, upper mandrel and the upper end of the lower mandrel; the annular expandable packer element having opposed ends, respectively, connected to be compressed between the element compressor and the cap, respectively; the upper marginal end of the lower mandrel sealingly engaging the upper mandrel and reciprocating therein upon rotation of the upper mandrel respective the lower mandrel; and a drain valve for controlling flow along a drain passageway formed from the central axial passageway into the variable chamber and through the element compressor to thereby control flow of well fluid through the drain passageway responsive relative rotation between the upper and lower mandrel.
 2. The packer device of claim 1, wherein the drain passageway includes an inner port formed in the upper mandrel and an outer port formed in the element compressor with the upper end of the lower mandrel forming sliding valve element that closes a port responsive to counterclockwise rotation and uncovers a port responsive clockwise rotation to thereby allow a dry string to be realized when running the packer device into and out of a conduit.
 3. The packer device of claim 2 wherein the packer device is removably connected to a tubing anchor device and mounted within a conduit.
 4. The packer device of claim 3, wherein there are axially spaced packer elements arranged between the element compressor and the cap; said lower mandrel being anchored to a conduit wall by the anchor device whereby counterclockwise rotation of the upper mandrel telescopingly moves the element compressor toward the cap to thereby expand the spaced packer elements radially outward into engagement with the conduit wall.
 5. The packer device of claim 1 and further including an annular groove formed within the outer surface of the lower mandrel, a carrier affixed to an inner wall of the upper mandrel for engaging the last said annular groove and thereby position a drain port therethrough in the upper mandrel in the closed position to preclude flow therethrough.
 6. A counterclockwise rotational set packer device forming part of a tool string insertable within a conduit; an upper mandrel having a marginal end telescopingly received respective a marginal end of a lower mandrel; a longitudinally extending axial passageway extending through the upper and lower mandrels; an annular element compressor, an annular resilient packer element, an annular cap, complementary counterclockwise threads formed between the upper and lower mandrels for telescopingly moving the upper and lower mandrels towards and away from one another upon rotating the upper mandrel respective the lower mandrel; the element compressor having opposed ends, with one end thereof being attached to the upper mandrel and forming an annular chamber therebetween; the cap being connected to a lower end of the lower mandrel in spaced relation respective to a lower end of the element compressor; the upper marginal end of the lower mandrel extending into and sealingly engaging a wall of the annular chamber, an outer and inner flow port, respectively, formed through the element compressor and the upper mandrel, respectively; one port being arranged respective the element compressor for flow therethrough to be obstructed by the lower mandrel upon setting of the packer and to be unobstructed when the packer is unseated, thereby equalizing the pressure between the longitudinal axial passageway and the exterior of the packer device when the upper and lower mandrels are telescoped apart, and to prevent flow through the ports when the upper and lower mandrels are telescoped together; the packer element being positioned between the element compressor and the cap for expanding the packer element upon counterclockwise rotation of the upper mandrel respective the lower mandrel while at the same time the upper end of the lower mandrel is moved to sealingly engage one of the ports and thereby preclude flow therebetween.
 7. The packer device of claim 6 wherein the inlet port is a radial port formed in the upper mandrel and cooperates with the upper end of the lower mandrel to form a sliding valve assembly that is moved to the closed position responsive to counterclockwise rotation and is moved to the closed position upon clockwise rotation of the upper mandrel to thereby allow a dry string to be realized when running the packer device into and out of a conduit.
 8. The packer device of claim 6 wherein axially spaced expansible packer elements are arranged to be compressed between the element compressor and the cap responsive to counterclockwise rotation; said lower mandrel being anchored to a conduit wall by an anchor device whereby counterclockwise rotation of the upper mandrel telescopingly moves the element compressor toward the cap to thereby expand the spaced packer elements into engagement with the conduit wall while the lower mandrel is held against rotation by the anchor device.
 9. The packer device of claim 6 and further including an annular groove formed within the outer surface of the lower mandrel, a carrier affixed to an inner wall of the upper mandrel for engaging the last said annular groove and thereby position the port inlet of the upper mandrel in a closed position to preclude flow therethrough.
 10. The packer device of claim 9, wherein axially spaced packer elements are arranged between the element compressor and the cap; said lower mandrel being anchored to a conduit wall by an anchor device whereby counterclockwise rotation of the upper mandrel telescopingly moves the element compressor toward the cap to thereby expand the packer elements into engagement with the conduit wall.
 11. The packer device of claim 6 wherein the passageway includes an inlet port formed in the upper mandrel and an outlet port formed in the element compressor with the upper end of the lower mandrel forming a sliding valve assembly that covers a port responsive to counterclockwise rotation and uncovers a port responsive clockwise rotation to thereby allow fluid to drain from the central passageway whereby a dry string to be realized when running the packer device into and out of a conduit; wherein axially spaced packer elements are arranged between the element compressor and the cap; said lower mandrel being anchored to a conduit wall by an anchor device whereby counterclockwise rotation of the upper mandrel telescopingly moves the element compressor toward the cap to thereby expand the packer elements into engagement with the conduit wall. 